Nitrogenous condensation product



"Patented se el'z, 1943 UNITED STATES PATENT OFFICE NITROGENOUSCONDENSATION PRODUCT Otto Grimm and Hans Ranch, Darmstadt, Germany,assignors to Riihm & Haas Company,

Philadelphia, Pa.

No Drawing. Application Angust 22, 1939, Serial No. 291,3:29. InGermanydugnst 23, 1938 13 Claims.

polymeric amide such as polymethacrylic amide,

an amine such as dimethylamine, and an aldehyde such as formaldehyde areall high molecular weight substances containing nitrogen. They aresoluble in water and form with acid dyes and ing at a temperature of 40to 50 C.-,.and then applying the dye. In many cases it is' advantageousto dry the impregnated fabric at higher temperatures, for example about100 C. before dyeing.

When dyeing fabrics, leather or other fibrous material, the dye may beapplied first, followed by treatment with the high molecular weight withnatural, synthetic and mineral tanning agents, compounds which areinsoluble inneutral and acid aqueous olutions. On account of theseproperties the new products are useful in dyeing fabrics, particularlycellulosic fabrics, and leath-.

er. They are also useful in the process of tanning because the insolubleproducts which they form with the tanning agents can be easily formedwithin the leather, thus yielding a good, full leather. a

It is known that cellulosic fabrics cannot be dyed directly with aciddyes. Many methods have been proposed for treating fabrics or fibers ofthis kind with basic substances so as to introduce basic groups into thecellulose molecule.

This is important becausevery often it is desirable to weave fabricsfrom two or more fibers, for example cotton and silk. Such fabricscannot be dyed with a single dye to a uniform color. If basic groups areadded to the cellulose molecule, then acid dyes can be used on mixedfabrics and uniform color obtained. Processes for treating cellulose soas to introduce such groups include treatment with ethylene lmine,epichlorhydrine followed by ammonia, impregnation with urea-formaldehydecondensation products, etc. These all have the disadvantage that thefabric must be subjected to a separate treatment to prepare it fordyeing with acid dyes. When using the products of the present inventionforthe purpose of fixing acid dyes on cellulosic fabrics, it is onlynecessary to impregnate the fabric with a solution of the condensationproduct and then treat the fabric with a solution of an acid dye. Bymeans of this treatment the dye is bound in the fiber. In some casesvery uniform dyeings can be achieved by first impregnating the fabric,either hot or cold, with the products of this invention,,wringing out,drynitrogenous products for the purpose of fixing the dye on the fiber.The lightfastness of such dyeings is much better than when the treatmentwith the new products is omitted.

When used for filling leather, the new condensation products have manyadvantages over the usual fillers such as kaolin, calcium carbonate,etc. These are usually drummed into the leather along with the fatliquor. The new ,products on the other hand may be added before the fatliquor and, since they form insoluble products with the tanning agent,the actual filling materialis formed directly in the leather. A singletreatment of the leather with these materials gives an improved productbut still greater improvement is obtained by using relatively largeamounts of the new products and then subjecting the leather to asecondtanning treatment. By this means more of the insoluble complex canbe incorporated and a fullerleather obtained.

The nitrogenous products of high molecular weight with which the presentinvention is concerned are prepared by reacting a polymeric amide suchas polymethacrylamide, an amine such as dimethylamine, and an aldehydesuch as formaldehyde in an acid, neutral or alkaline medium. It ispreferable, however, to carry out the reaction in a slightly acid mediumin which case the amine is employed in the form of one of its salts.

The amines which can be used in preparing these condensation productsare those which ample, amino acids, may also be used in the' reaction.

Formaldehyde is preferred for condensing with the polymeric amide andthe aliphatic amines or polymers which yield aqueous solutions of low tointermediate viscosity because, if solutions of high viscosity areemployed, difficulties in handling may arise. Joint polymers of theunsaturated acid amides and other polymerizable materials such asacrylic, methacrylic andvinyl esters may be employed, in which case careshould be taken that the joint polymer contains a sufilcient proportionof amido groups to render it soluble in water. Water-soluble materialsobtained by the partial alkaline hydrolysis of polymeric acid nitriles,such as polyacrylic nitrile may also be used provided they contain asufiicient proportion of amido groups. Such compounds probably containunchanged nitrile groups as well as some carboxyl groups. Such compoundsmay be considered to be joint polymers of acrylic amide and acrylicacid. They are useful in the present invention but are not so efiectiveas polymers containing a larger proportion of amido roups.

The relative amounts of the reactants can be varied as it is not alwaysnecessary to use them in exactly equivalent amounts. However, the amountof aldehyde chosen should be such that there is not much excess, whichcan be detected by the odor, in the final solution.

Both organic and inorganic acids may be used to establish the desiredhydrogen ion concentration in the reaction mass. 0f the inorganic acidsthose of intermediate strength are preferable, particularly sulfuric,phosphoric, meta-phosphoric, pyrophosphoric, and other polyphosphoricacids. When such acids are employed, the pH of the aqueous solution inwhich the reaction takes place should be adjusted to about 4. Theorganic acids are preferably the aliphatic carboxylic acids and may bemonobasic or polybasic. They may also contain hydroxyl groups. Examplesof such acids are formic, acetic, propionic, butyric, oxalic, lactic andtartaric acids. When organic acids are used, the .solution in which thereaction takes place should be less strongly acid then when theinorganic acids are employed. A pH of 6 to 6.5 is desirable for theorganic acids.

When an acidic medium is employed in the initial stages of the reaction,it is preferable to employ a weak acid, such as acetic acid, because theprecipitate, which forms momentarily when, for example, the thirdingredient is added to the reaction mixture of the other two, dissolvesmore readily in the presence of a weak acid. The process may also .becarried out in the presence of strong acids and the products so obtainedare particularly suitable for fixing tanning mate- The order in whichthe reactants are mixed maybe varied. For example, the amine may firstbe neutralized and the solution made slightly acid, after which thealdehyde is added and then the polymeric amide. If desired, thepolymeric amide may be added to the amine solution followed by thealdehyde. The amine and the aldehyde may be reacted in the absence ofacid and the polymeric amide added to the product In this case thereaction product of amine and aldehyde may be acidified before theaddition of the amide. The polymeric amide may be reacted with thealdehyde and the amine reacted with this product with or without theaddition of acid.

The nitrogenous condensation products made according to the inventionmay be used, as pointed out above, for filling leather because theyreact not only with vegetable tans but also with those prepared fromsulfite cellulose extracts, synthetic and mineral tans. Because of thefact that the new products are universal precipitants for all of thesetanning agents they have many advantages over precipitantspreviously-used,

such as glue. Glue has the disadvantage when used for this purpose that,whereas it precipitates the vegetable tans, it does not precipitate allsynthetic tans, unless these have been treated in some way to yieldinsoluble products with the glue. The precipitation of some synthetictans by glue can be prevented by the presence of sulfite cellulose tans.This is understandable because the sulfite cellulose extracts are neverprecipitated by glue.

For precipitating tanning agents with the products made according to theinvention, the pH of the solution may vary from 4.0 to 7.3 but ispreferably adjusted to about 5.5. This range is practically the same asis used in preparing the products so that in many cases the solution inwhich the reactions are carried out may be employed without furthertreatment. When products which have been made in the absence of acid areto be used as precipitants, sufiicient acid should be added before orduring precipitation so as to adjust the solution to the proper pH.

The precipitates formed from the new products and tanning agents aresoluble in alkaline solutions, for example in ammonia, but arereprecipitated when these solutions are acidified. When using theproducts to precipitate sulfite cellulose tans about equal parts byweight of the two reagents are used calculated on the dry material.

Generally speaking, the precipitants should be used at concentrations ofless than 10%I P eferably about 4%, for the fixation of tanning agentsin leather because, it higher concentrations are used, there is dangerof the leather becoming tacky.

When usedas a mordant for dyeing leather, textiles, etc., the newproducts result in a. fuller coloring and a fixation of the dye on thesurface.

The new products thus have a wide field of application. They may, as hasbeen indicated above, be used to precipitate certain materials on animalfibers. They may also be used for the same purpose on other fibrousmaterials, such as paper and textiles. The presence of fiber is notessential. Soluble dyes may, for example, be precipitated from theirsolutions thus yielding colored pigments and tanning agents orpolymethacrylic amide may be precipitated in the form of an adherentmass, the adhesive properties ofwhich may be varied or eliminated bysuitable changes in its composition.

The following examples will illustratethe invention which, however, isnot limited to the exact reagents and conditions of reaction given as itmay be otherwise practiced within the scope of the appended claims.

may be used.

Example 1 135 parts by weight of a aqueous solution of polymethacrylicamide is added in portions. In place of the polymethacrylic amide, amixed polymer made from methacrylic amide and a small amount ofmethacrylic acid or acrylic acid The resulting solution may be used toprecipitate the lignin-sulfonic acid from crude sulfite liquors, forexample 1000 g. of the crude liquor are treated with 94 ccm. of theabove solution and 400 com. of water. The resulting precipitate isfiltered and dissolved in 40 com. of 2.5% ammonia. Any undissolvedmaterial is filtered. The clear solution may be used for fillingleather. By making slightly acid the material is reprecipitated and isfixed in the leather in an insoluble condition. p I

The ammoniacalsolution may also be used for impregnating textiles,paper, artificial leather,

etc.

In place of ammonia, other alkaline compounds may be used, for-example','sodium hydroxide or dimethylamine.

Example-2 '50 g. of as dimethylamine solution is mixed with 80' g. of96% acetic acid giving a solution having a pH of about 6. To thissolution 3..

. of formaldehyde is added and the solution heated. To this there isadded, in portions,. 100

g. of a 10% aqueous solution of polymethacrylic amide. Before theaddition of a further portion the precipitate which forms must beredissolved valueof about 5.2.

The solution may be used as an assistant in dyeing; for example,chrome-tanned leather is by'boiling. .The product thus obtained has a pHneutralized as usual and .mordanted with one 125g. of ortho-phosphoricacid (tech. cone.)

is added slowly to 300 g. of dimethylamine. The solution is heated and300 com. of 30% form--' aldehyde added. 1000 g. of 10% aqueous solu- 30%dimethylamine. The resulting solution has a pH of about 4. This solutionis boiled and 110 parts of a 10% aqueous solution of polymethacrylicamide added in portions. The resultin solution may be used forfilling ofchrome leather. This can be carried out as follows:

The skins after the usual pickling are pretanned with 80% of water, 2%of salt, and 3% of chrome alum calculated on the weight of the skins.The skins are then drummed in a fresh bath consisting of 10% of theabove solution and 20% of water. After an hour the skins are tanned inthe usual way with a basic chromium tanning material. This processyields a chromeleather with a full feel and a firm grained flank.

.Erample 5 g. of 30% formaldehyde is added to 90 g. of 35% aqueousdimethylamine solution. To this solution there is added while heating180 g. of a 10% aqueous solution of polymethacrylic amide in portions.Before each addition the precipitate resulting from the previousaddition must be dissolved by boiling. This solution is.acidified by theaddition of 144 ccm. of 96% acetic acid and may then be used for fixingtanning materials or asan assistant in dyeing.

' Example 6 0.21 parts by weight of a'2.5% aqueous soluamide. Afterheating for some time agood precipitating agent for tanning material isobtained.

The furfurol may be replaced by crotonaldehyde, acetaldehydeorallylaldehyde.

. Example 7 0.5 parts byweight of 85% of ortho-phosphoric acid arestirred with 5.3 parts by weight of a 3.3% aqueous solution offl-naphthylaminehydrochloride and'the resulting mash of crystals tion ofpolymethacrylicamide is added, in portions, to the hot solution. Beforethe addition of any portion the precipitate'formed from' the previousone must be re'-dissolved by boiling.

The resulting solution may beused for filling leather tanned withsynthetic tans, e. g., condensation productsofphenolor cresolsulfonicacid with formaldehyde, condensation products of the sulfonic acids ofnaphthalene and its homologues with formaldehyde, phenol-aldehyde condensation products, condensation products of Example4 1 22 parts by weightof 30% aqueous formaldehyde solution is added to 45 parts by weight of vdimethylamine sulfate solution containing about is dissolved by heating0.5 part of a 2.5% aqueous solution of furfurol are added to the clearsolution whilst stirring, followed by one part of a 10% solution ofpolymethacrylic amide. After heating for some time a product is obtainedwhich can be used for fixing acid dyes and tanning materials containingacid groups.

- Ewample 8 .0.05 .part by weight of acrolein are first stirred with 5.3parts by weight of 3.3% aqueous solution; ofp-naphthylaminehydrochloride. 0.5 part by weight of 85% ortho-phosphorieacid and then 1 part by weight of a 10% solution poly methacrylic amideare added. After heating for some time a product is obtained which is agood precipitant for acid dyes and tanning materi- "als containing acidgroups.

This'solution may beused to fix dyes on cotton, artificial silk or linenfabrics. The fabric is first treated with the solution and. the dye isthen applied at about C. The linen may be dyed with a 0.2% solution ofDiamine pure blue FF (Schulz Farbstofftabellen, vol, 1, No. 510). Theartificial silk. may be dyed with a 0.05% solution of Chrome Leatherblack RW extra (Schulz Suppl. vol. 1, page '71). The'cotton may be dyedwith a 0.2% solution of the diamine pure blue or with a 0.1% solution ofBenzo dark green B (Schulz, vol. II, page 32, and Suppl..vol. II, page1.24). The colors thus obtained are much faster than those obtained withthe same dyes on untreated fabrics.

Example 9 2.5 parts by weight of propylamine are mixed with 1.1 parts byweight of 85% formic acid and 2.5 parts by weight of 30% formaldehydeare added. After heating, parts of a 10% aqueous solution of aninterpolymerization product consisting of 80 parts by weight ofpolymethacrylic amide and 20 parts by weight of methylacrylate are addedin portions. The insoluble residue is filtered oflL The solution may beused for prev cipltating tanning materials from sulfite pulp.

Example 11 5 parts by weight of 33% ethylamine are mixed with'2 parts byweight of concentrated sulphuric acid and 3.2 parts by weight of 30%formaldehyde are added to this solution while stirring. After heating,10 parts by weight of a 10% aqueous solution of an interpolymerizationproduct consisting of '75 parts by weight of polymethacrylic amide and25 parts by weight ethylmethacrylate are added in portions and theheating is continued. The product may be used for the precipitation oftanning material.

Example 12 138-parts by weight of 42% dimethylamine are heated withparts by weight of 30% formaldehyde for 2 to 3 hours under a refluxcondenser until the liquid which is first cloudy has become absolutelyclear, To'this alkaline solution are added while stirring 2130 parts byweight-of a 3.3% aqueous solution of polyacrylic nitrile which has beensaponified with 65% of the amount of soda lye necessary for completesaponification, and 50 parts by weight of 30% formaldehyde.

After heating. for 30 minutes the solution is rendered acid with 11parts by weight of 96% acetic acid to pH 5.

The product may be used for fixing tanning material.

Instead of the 3.3% aqueous solution of polyacrylic nitrile there may beused a 3.3% aqueous solution of an interpolymerization product of 10parts by weight of methylmethacrylate and 90 parts by weight of acrylicnitrile which has been saponified with of the amount of alkali necessaryfor complete saponification,

Example 13 .21 parts by weight of 50% dibutylamine are mixed with 14'parts by weight of orthophosphoric acid. To the solution are added 7.5parts by weight of 30% formaldehyde. After heating, 42.5 parts by weightof a 10% aqueous solution of polymethacrylic amide is added in Example14 30 parts by weight of 50% cyclohexylamine are mixed with 21 parts byweight of 96% acetic acid,

To this solution are added 7.5 parts by weight of 30% formaldehyde.After heating, 42.5 parts by weight of a 10% aqueous solution ofpolymethacrylic amide is added infportions while stirring and theheating is continued until the solution becomes absolutely clear.

Example 15 25.5 parts by weight of 50% piperidine are mixed with 12.5parts by weight of 85% formic acid, To this solution 4.2 parts by weightof allylaldehyde is added. While heating and stir:- ring, 42.5 parts ofa 10% aqueous solution of polymethacrylic amide is added in portions andthe heating is continued until the solution becomes absolutely clear.

Example 16 32 parts by weight of 50% benzylamine andand washed out asusual and then drummed for one hour with 100% of water (calculated onthe shaved weight) and one per cent of th solution prepared according toExample 2.

After this time the leather is dyed in a fresh bath with 1% Acid leatherbrown EG (Schultz FarbstofiZ-Tabellen, vol. II, P ge, 189) and 100% ofwater at 65 C. After the complete absorption of the dyestufi the leatheris fatliquored, usually in a. fresh bath. A particularly full and evendyeing is obtained.

Example 18 Chrome tanned glove leather is neutralized, washed out andfatliquored as usual and then drummed for one hour in a fresh bath with100% of water and 2% of the solution prepared according to Example 2.

Then the leather is dried and wet back. It is then drummed with 100%water of 65 C. (calculated on the weight of the wet leather), 0.8%

lution has become absolutely clear.

Cotton brown RVN; 0.8% Cotton brown GNJ (Schultz Farbstoff-Tabellen,vol. II, page 30 and Suppl. vol. II, Pa e 123) and 0.5% Acid leatherbrown EGR (Schultz Farbstoff-Tabellen, Suppl. vol. II, page 240). untilthe dye solution is completely exhausted. The leather is thenfatliquored, set out and dried as usual.

This treatment of the leather causes a complete absorption of the dye.

Example 19 g. of desized rayon staple fiber are drummed with 250 g. ofthe impregnation product prepared according to Example 2 and 250 com.waterfor v5 minutes and then pressed. It is dried at 3040 C. and dyedwith a solution containins 1 g. Acid anthracene brown RH extra (SchultzFarbstoff-Tabellen, vol. I, Nr. 134) to 1 liter water at 90 C., thenwashed and dried.

The resulting color is much fuller than when the impregnation product isomitted.

Example 20 500 g. of desized rayon staple fiber are drummed -with 800 g.of the impregnation product prepared according to Example 2 and 800 com.water for 5 minutes and then pressed. It is dried at 45-50 C. and dyedwith a solution containing 2 g. Nigrosin WLA (SchultzFarbstoff-Tabellen, vol. I, Nr. 986 and Suppl. vol. II, page 56) to 1liter water at 90 C., then washed and dried.

This acid dye cannot be fixed directly on the desized rayon staple fiberbut after impregnation of the fiber with the product described inExample 2, the dye can be permanently fixed.

Subject matter pertaining to the use of the condensation products of apolymeric amide, an amine and an aldehyde in the treatment of leather isclaimed in application Serial No. 291,- 328, filed August 22, 1939, nowPatent 2,205,355. Subject matter relating to the use of thesecondensation products in the dyeing of fabrics and leather is claimed incopending application Serial No. 291,327, filed August 22, 1939.

We claim:

1. The process of preparing nitrogenous materials of high molecularweight which comprises reacting by condensing together a non-aromaticamine having at least one hydrogen atom attached to the nitrogen atomthereof, an aldehyde, and a water-soluble polymeric amide.

2. The process of preparing nitrogenous materials of high molecularweight which comprises reacting by condensing together an aliphaticamine having at least one hydrogen atom attached to the nitrogen atomthereof, an aldehyde, and a water-soluble polymeric amide.

3. The process of preparing nitrogenous materials of high molecularweight which comprises reacting by condensing together in an aqueoussolution at a pH of about 4 to about, 7.3 an aliphatic amine having atleast one hydrogen atom attached to the nitrogen atom thereof,formaldehyde, and a water-soluble polymeric amide.

4. The process of preparing nitrogenous materials of high molecularweight which comprises reacting by condensing together in aqueoussolution a secondary aliphatic amine, formaldehyde,and a water-solublepolymeric amide.

5. The process of preparing nitrogenou materials of high molecularweight which comprises reacting by condensing together in an acidicaqueous solution dimethylamine, formaldehyde, and polymeric acrylamide.

6. The process of preparing nitrogenous materials of high molecularweight which comprises reacting by condensing together in an acidicaqueous solution dimethylamine, formaldehyde, and polymericmethacrylamide.

7. The process of preparing nitrogenous materials of high molecularweight which comprises reacting by condensing together in an aqueoussolution at a pH of about 4 to about 10 a watersoluble polymeric amideresulting from the partial hydrolysis of polyacrylonitrile,formaldehyde, and dimethylamine.

8. The product obtained by condensing together a non-aromatic aminehaving at least one hydrogen atom attached to the nitrogen atom thereof,an aldehyde, and a water-soluble polymeric amide.

9. The product obtained by condensing together in an aqueous medium analiphatic amine having at least one. hydrogen atom attached to thenitrogen atom thereof, an aldehyde, and a water-soluble polymeric amide.

10. The product obtained by condensing together in an aqueous medium asecondary aliphatic amine, formaldehyde, and a water-soluble polymericacrylamide.

11. The product obtained by condensing toether in an aqueous medium asecondary aliphatic amine, formaldehyde, and a water-soluble polymericmethacrylamide.

12. The product obtained by condensing together dimethylamine,formaldehyde, and a water-soluble polymeric methacrylamide.

13. The product obtained by condensing together dimethylamine,formaldehyde, and a water-soluble polymeric amide resulting from partialhydrolysis of polyacrylonitrile.

I OTTO GRIMM. HANS RAUCH.

